Merge remote-tracking branch 'origin/master'

# Conflicts:
#	src/main/java/org/orekit/rugged/api/Rugged.java
#	src/main/java/org/orekit/rugged/errors/RuggedMessages.java
#	src/main/java/org/orekit/rugged/refraction/AtmosphericRefraction.java
#	src/main/java/org/orekit/rugged/refraction/MultiLayerModel.java
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_de.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_en.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_es.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_fr.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_gl.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_it.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_no.utf8
#	src/main/resources/assets/org/orekit/rugged/RuggedMessages_ro.utf8
#	src/test/java/org/orekit/rugged/errors/RuggedMessagesTest.java
#	src/test/java/org/orekit/rugged/refraction/MultiLayerModelTest.java

src/main/java/org/orekit/rugged/api/Rugged.java

@@ -55,6 +55,7 @@ import org.orekit.rugged.linesensor.LineSensor;
 import org.orekit.rugged.linesensor.SensorMeanPlaneCrossing;
 import org.orekit.rugged.linesensor.SensorPixel;
 import org.orekit.rugged.linesensor.SensorPixelCrossing;
+import org.orekit.rugged.refraction.AtmosphericRefraction;
 import org.orekit.rugged.utils.DSGenerator;
 import org.orekit.rugged.utils.ExtendedEllipsoid;
 import org.orekit.rugged.utils.NormalizedGeodeticPoint;

src/main/resources/assets/org/orekit/rugged/RuggedMessages_de.utf8

@@ -72,7 +72,7 @@ TILE_ALREADY_DEFINED = <MISSING TRANSLATION>
 
 # unknown tile {0}, line {1}, file {2}: {3}
 UNKNOWN_TILE = <MISSING TRANSLATION>
- 
+
 # no parameters have been selected for estimation
 NO_PARAMETERS_SELECTED = <MISSING TRANSLATION>